Inkjet printing mechanisms may use cartridges, often called “pens,” which eject drops of liquid colorant, referred to generally herein as “ink,” onto a page. Each pen may include a printhead formed with very small nozzles through which the ink drops are fired. To print an image, the printhead is propelled back and forth across the page, ejecting drops of ink in a desired pattern as it moves. The particular ink ejection mechanism within the printhead can include a piezo-electric or a thermal printhead mechanism.
The inks used in an inkjet printer may be supplied from a reservoir of an inkjet cartridge. Some cartridges are monochrome and carry a single color such as black ink. Other cartridges are multi-color, and may include reservoirs that carry the three ink colors of cyan, magenta and yellow used for mixing, with black ink, to form most other colors. The multi-color cartridges maybe said to include three color “pens” while the monochrome color cartridges include one “pen”. There are also printing mechanisms that use four monochrome cartridges. In systems that use multi-color cartridges, when one of the “pens” or color reservoirs is emptied, the entire cartridge is replaced. The result is that any remaining color in any unemptied reservoir is wasted.
The choice of colors to use and print may be designated by the computer user. In some instances, the colors selected are fixed, such as for color pictures, natural images, logos or replications. In other instances, the colors selected for printouts maybe based on the preference of the computer user. The personal preference of the computer user may lead to repeated use of a particular color scheme that may empty the ink in one reservoir and result in wasting the ink in other reservoirs. For example, a user that makes many presentations as part of his job may use one favored color scheme for most of the power point slide presentations he develops. The preferred color scheme can be one of several color scheme templates that is part of the presentation software or the preferred color scheme may be totally selected by the computer user. In any event, repeated use of a color scheme can lead to wasted ink in one or more of the reservoirs of a multi-color cartridge.